rt = int(input())

if rt >=30:
    print("Yes")
else:
    print("No")
     rt = int(input()) rt int(input()) int input() input if rt >=30:
    print("Yes")
else:
    print("No")
     rt >=30 rt 30 print("Yes") print "Yes" print("No") print "No" rt = int(input()) int(input()) rt
rt = int(input())

if rt >=30:
    print("Yes")
else:
    print("No")
    
